ANALYSIS OF ANTI-SUBMARINE ACTION BY AIRCRAFT.
 
  Unit.     VP-74        Unit Report No.      10        Aircraft Type:    PBM-3C  
     
  Aircraft No.      74-P-6  
     
  Aircraft Commander:      Lieutenant H.S. Davis, USNR.  
     
  Location of Attack - Latitude            11-00 S.  
                                  Longitude         35-36 W.  
     
  Date:    May 17, 1943.  
     
  Time:    0850 (Zone plus 3).  
     
      1.   The airplane was flying at an altitude of 4500 feet on a concentrated air-surface hunt for a submarine suspected in the area for one week and which had been attacked the previous afternoon.  The weather was good with unlimited visibility, and only scattered clouds.  Radar contact was obtained on a fully surfaced submarine at a range of 18 miles on the starboard bow.  Visual contact was obtained almost immediately thereafter.  Full power was applied immediately, and course was changed slightly in order to take advantage of the sun gage.  The submarine, steaming on a somewhat closing course, started to crash dive when the plane was slightly less than 2 miles away and disappeared from sight while the range was still 3/4 mile.  Fifteen seconds after the conning tower disappeared 6 Mark 44 depth bombs with fuses set for 25 feet were released by intervelometer control with a corrected spacing of 82 feet between impacts.  At the time of release the airspeed was 197 knots, the altitude was 60 feet, and the target angle was 500.  The resulting six explosions were observed to straddle the submarine’s projected track about 150 to 200 feet ahead of the swirl.  Shortly thereafter a large mass of air bubbles was noticed adjacent to the forward edge of the bomb slick.  A few minutes later the submarine was seen to come to the surface about 1/4 mile ahead and slightly to the left of the point of the attack and on a reverse course.  Very shortly thereafter another plane in the area delivered a most effective attack.  The plane remained in the area for over 5 hours following the attack, during which time the pilot coordinated the strafing activities of the two planes present, led surface vessels to the scene, and assisted the surface vessels in locating and rescuing survivors.  
     
 

    2.   The execution of this attack is excellent in every respect, and the manor in which this pilot coordinated activities subsequent to the attack is considered outstanding.  The bomber who released the bombs is considered jointly responsible for the accuracy obtained.  The report of the action was very complete and very well prepared, and the comments of the squadron commander are concurred in.

  
     
      3.   It is noted that this action occurred at the end of a seven and one-half day hunt which was started following an RDF contact.  During this time the area was frequently traversed, and the possibly suspicious activities of a merchant vessel were observed.  Several radar contacts which disappeared and an unproductive night sighting of a “V” shaped wake were obtained.  About 18 hours before this action an attack had been delivered on a submarine at a position about 24 miles to the westward.  While it is difficult to state with any degree of certainty that all contacts were made upon the same submarine, the efforts of the concentrated hunt certainly bore welcome fruit.  
     
 
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ANALYSIS OF ANTI-SUBMARINE ACTION BY AIRCRAFT.
(Continued)
 

 

  
      4.   In view of the circumstances surrounding the surfacing of the submarine subsequent to the bombing it is considered that as a result of this attack the submarine was probably damaged.  In any event, this attack brought the submarine to the surface and placed it in an excellent position to receive the lethal blow delivered by the accompanying plane.  The pilot and bomber on this attack are considered jointly responsible with the pilot of the accompanying plane for the results of the coordinated action.  
     
     
     
     
     
     
     
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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